wurts



(No Model) A. J. WURTS.

DEVICE FOR PROTECTING ELECTRIG UIRUUITS.

No. 574,979. Patented Jam 12, 1897.

WITNESSES: l/VVE /VTOR wwwww MZ W ATTORNEYS.

UNITED STATES PATENT OFFICE.

ALEXANDER JAY VURTS, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO THE VESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, OF SAME PLACE.

DEVICE FOR PROTECTING ELECTRIC CIRCUITS.

SPECIFICATION forming part of Letters Patent No. 574,97 9, dated January 12, 1897.

Application filed OCIZOllI' 2,1895. Serial NO. 564,404. (N model.)

To all whom, it may concern: view of the coil, showing also the circuit con- Be it known that I, ALEXANDER JAY nections. \VURTS, a citizen of the United States, resid- Reference being now had to the details ing in Pittsburg, in the county of Allegheny shown in the drawings, 1 is a cylinder or core and State of Pennsylvania, have invented a formed of wood or other insulating material new and useful Improvement in Devices for and provided with a helical groove 2 for the Protecting Electric Circuits, (Case No. 670,) reception of the bare wire 3, constituting the of which the following is a specification. coil proper. The core 1 has fastened to it at My invention relates to that class of appaeach end by means of a screw l a base-piece IO ratus which is employed for protecting elecor standard 5, by means of which the coil may trical circuits and connected machines and be fastened in position upon any desired base apparatus from the injurious effect of static or support. charges derived from the atmosphere; and it (5 is a plate or strip formed of fiber or other has for its object to produce an apparatus for suitable insulating material and provided,

15 this purpose which will be more certain and with a narrow longitudinal slot 7, extending effective in operation than have been the de nearly throughout its length. Located upon vices heretofore usually employed. this strip of insulating material is a strip or I have found by experiment that the static plate 8 of some good conducting material, pressure or tendency to discharge varies in preferably copper, which is approximately of 20 intensity at different points in a given length the same width and length as the insulatingof conductor, and that such points are apt to strip 6. As shown in the drawings, one end occur atirregular intervals. In view of these of this conducting-strip Sis bent into contact conditions I have been led to believe that the with the end turn of the coil 3; but it may tendency to discharge is due to the oombinabe a straight strip held out of contact with 25 tion of a greater or less number of series of all of the turns over which it is placed, if dewaves the algebraic sums of which give resired. sultant pressures for which it is necessary to Suitably fastened to the upper side of the provide discharge-paths to the ground. strip, preferablyby means of solder, is a bind As it is impossible to determine in advance ing-post 9, this binding-post serving to con- 30 at just what point or points the greatest presnect one end of the conductor 10 to the strip 8. sure will be exerted, I propose to introduce a It is to be understood that devices materichoke-coil into the line which will act to imally different in form and dimensions from pede the passage of the static charge along the parts 6 and 8 may be employed, if desired, the line conductor and to provide a considerthe invention being in no wise limited as re- 3 5 able number of discl1argepaths arranged at gards the specific construction of these de frequent intervals along the coil, in order to vices. insure the intercepting of some, at least, of 11 is a lightning-arrester, one side of which the points of highest pressure. I propose to is connected to the conductor 10 and the other also interpose a spark-gap in each dischargeside to one end of the conductor 2, the other 40 path, unless a lightning-arrester is included end being grounded, as shown. The coil 0 in the ground-conductor, in order to prevent and strips (3 and 8 are preferably wound with the passage of the dynamo-current and the an insulated covering 13, in the present inconsequent short-circuiting of the coil. I11 stance shown as applied in the form of tape, any event the introduction of the spark-gap which is wound spirally around the coil and 45 is necessary in all but one of the dischargecore and serves to complete the insulation of 5 paths referred to. the coil and also to protect it and hold the In the accompanying drawings, Figure 1 is strips 6 and 8 in position thereon. a choke-coil, shown partially in section and It will be understood that the lightning-arpartially in side elevation, constructed in acrester 11 may be omitted from the organiza- 50 cordance with myinvention. Fig. 2 is aplan tion 5 but in such case it will of course be es sential to keep all parts of the strip 8 out of contact with the coil 3.

It will be readily apparent from the con struction shown and. described that a small spark-gap is interposed between each turn but one of the coil 3 over which the strip 8 extends and. that a single path for the static discharge is provided from the strip 8 to the ground.

As shown in the drawings, I prefer to leave several turns of the choke-coil at the end nearest the machine or apparatus to be protected unprovided with discharge-paths, and consequently extend the strips 6 and 8 over a portion only of the length of the coil, this construction being adopted in order to prevent the return of a discharge or portion of a discharge from the coiulueting-strip 8 around the end of the coilto the line. \Vith the construction shown the distance between the end of the coil nearest the machine (indicated diagrammatically at 14) and the eorrcspoi'iding end of the conducting-strip Sis sufficient to preclude the jumping of a discharge from the conductor around the end of the coil to the line and thence to the machine.

\Vhile I have illustrated and described a specific combination and arrangement of parts as embodying my invention, I desire it to be understood that the invention is not limited to the details shown, which may be considerably varied in practice, if desired.

I claim as my invcntion l. The combination with a lightningarroster having a ground connection, of a chokecoil, and a conductingstrip extending along said coil for a portion of its length whereby spark-gaps are formed between the same and the adjacent turns of the coil, and an electrical connection between said strip and the lightning-arrestcr.

2. A cholce-coil provided with a conducting piece or strip located adjacent to but not in contact with several of the turns thereof,

whereby sparl-z-gaps are formed between said 4 turns and said strip.

3. A choke-coil provided with a conducting piece or strip located adjacent to, butnot in contact with, several consecutive turns thereof, whereby spark-gaps are formed he- 5 tween said turns and said strip, in combina tion with a lightning-arrester interposed between said piece or strip and the ground.

t. A choke-coil provided with a conducting piece or strip adjacent to several of the 5 turns thereof and a slotted. insulatingstrip interposed between said conducting-strip, and said turns, in combination with a lightniug-arrester interposed between said cenducting-strip and the ground.

5. The combination with a lightning-arrester, of a choke-coil provided with a slotted strip of insulating material in contact with several of the turns thereof, a ctmductingstrip on said insulating-strip and an insulat ing-covering for said par b. A choke-coil comprising a helicallygrooved core formed of insulating material, a coiled, bare conductor seated insaid groove, a conductiug-strip located adjacent to but out of contact with said bare COlltllltftOl' and provided with a binding-post, and an insulating-covering for said coil and strip.

7. A choke-coil comprising a helicail w grooved cylinder, a coiled bare conductor seated in said groove, a slotted strip of insulating material. extending longitiulinztlly of said cylinder for a portion of its length, a eonductingstrip upon. said insulating-strip,

and a protecting and insulating covering wound upon said parts.

In testimony whereof I have hereunto subscribed my name this 27th day of Septemlmr, A. l). 1895.

ALEXAN DIIG It Witnesses:

LnoN Ln Pomoi, Janus 1-3. Yocxo. 

